Livestock Science最新文献

Brazil and France, which are two major beef players, continue to consolidate and strengthen their respective positions on international beef markets. This review summarizes Brazil's and France's recent technological developments in this sector, tracing the recent evolution of their beef markets with attention to indicators of quality, meeting consumer expectations, as well as to future trends in new techniques for predicting beef sensory quality. In addition, this review will focus on the feasibility of implementing the Meat Standards Australia (MSA) grading protocols (known internationally as the Guaranteed Global Grading (3G protocols) by the International Meat Research 3G Foundation. Implementations of the MSA/3G grading scheme as recommended by the United Nations Economic Commission for Europe (UNECE) are particularly attractive because of MSA's proven record of increasing the reliability and accuracy of predictions of the sensory quality of beef through the use of pre- and post-slaughter factors. Additionally, the feasibility of new technologies for assessing the eating quality of beef has been evaluated by comparing the marbling scores of beef given by accredited graders for the MSA/3G method with those obtained using portable devices based on these new technologies. In this way, it is expected that implementation of the MSA/3G methodology and nondestructive techniques to evaluate the quality and safety of beef in Brazil and France will more reliably predict and further improve sensory quality, similar to what has already been implemented elsewhere.

The C-type natriuretic peptide (CNP) plays a central role in regulating the meiotic progression of oocytes into growing follicles in mammals. However, there are few reports examining the relationship between CNP and embryonic development. In our study, different concentrations (50, 100, or 150 nM) of CNP were added during in vitro maturation (IVM) of cumulus-oocyte complexes (COCs) or in vitro culture (IVC) of the bovine embryos (B. taurus indicus). The effects on embryo production and transcript abundance of the 20 genes of greatest interest that are related to metabolism, oocyte maturation, follicular development, cell signaling, oxidative and thermal stress, maternal-fetal interaction, and epigenetic regulation were evaluated. The blastocyst rate was influenced by CNP treatment (P = 0.049). Blastocyst rates were 31.05% (136/438) in the control group, 33.47% (162/484) in the 50 nM treatment group, 35.24% (179/508) in the 100 nM treatment group, and 32.53% (162/498) in the 150 nM treatment group for IVM. Furthermore, with IVC CNP supplementation, blastocyst rates were 28.49% (100/351) at 50 nM, 27.67% (119/430) at 100 nM, and 26.92% (112/416) at 150 nM. Moreover, the expression of RE1 silencing transcription factor (REST), a gene related to pluripotency and to embryonic development, was greater (P = 0.028) in response to 150 nM CNP supplementation in IVM. Finally, we observed for the first time the expression of the CNP receptor (NPR2) in embryos and the possible action of CNP at this stage. In conclusion, our data provide a reference for the improvement of IVM results in the in vitro production of bovine embryos with supplementation with 100 nM CNP, and this is the first study to demonstrate the expression of the CNP receptor (NPR2) in bovine embryos.

Differences including reproductive efficiency have been proved existence between high-altitude yak (Bos grunniens) and low-altitude cattle (Bos taurus), however, the discrepancies of ovarian follicles across them are still elusive. In the present study, RNA-seq results exhibited an obvious separation of yak and cattle granulosa cells (GCs), and 2329 differently expressed genes (DEGs) was obtained, with 1297 upregulated and 1032 downregulated DEGs in yaks. Advanced analysis revealed that DEGs were mainly enriched in cellular structure, DNA packaging and remodeling (GO and GSEA), hypoxia adaptability, energy metabolism (KEGG and GSEA), and epigenetic modification of histones (Reactome and GSEA). Metabolite profiles of yak and cattle follicular fluid (FF) were depicted by LC-MS/MS non-target metabolomics, and 350 different metabolites (DMs) were acquired, with 242 upregulated and 108 downregulated DMs in yaks. The KEGG pathway enrichment results demonstrated that DMs were primarily enriched in metabolism including lipid, carbohydrate and nucleic acid metabolism. Finally, twenty-nine pathways were significant enriched via integrative analysis, most of which were associated with metabolism including carbohydrate metabolism (e.g. Glycolysis / Gluconeogenesis) and lipid metabolism (e.g. Sphingolipid metabolism). Of note, the key hypoxia adaptation pathway, HIF-1 signaling pathway, was predominant enriched. Overall, we ascertained that the heterogeneity in ovarian follicles of yaks and cattle was existence, which were mainly reflected on hypoxia adaptation and energy metabolism. These results implied that the above processes were evolved specifically for the normal development of yak follicles under plateau atmosphere.

Recognizing the pivotal role of mating in animal breeding, this study strives to establish a robust strategy for recommending optimal matings among bovines. This strategy is built to maximize a single value derived from the economic selection index of full-cycle system in Brangus cattle. The study endeavors to apply computational methodologies to explore economically significant traits comprehensively, thereby leading to amplified financial gains for Brangus cattle breeders. Anchored within this overarching objective, a strategic deployment of a genetic algorithm is employed to formulate mating recommendations that precisely align with the priority traits designated by the genetic evaluation program of the Brazilian Brangus Association (BBA). The data set of the BBA for the simulations in this study encompass a range of selection criteria, including: i) birth weight; ii) mature cow weight; iii) ribeye area; iv) subcutaneous fat thickness; v) subcutaneous fat thickness at the rump; vi) escape speed; vii) nematode egg count per gram of feces; and viii) tick count. The research findings underscore that the recommendations provided by the computational strategy converge to increase the bioeconomic index while controlling the trade-off between this index and progeny inbreeding.

The relationship between feed efficiency at young ages and resilience as cows has been examined using an experiment that combines residual feed intake (RFI) evaluation of beef heifers and subsequent dietary challenge as cows. Feed efficiency of 569 heifers of 22 months of age was estimated during a 70-day period. Then a dietary challenge was applied on 303 of these animals after their first calving, half of them being fed 30 % below their expected needs from 10 days after calving up to the start of the grazing period (around mid-April), after which all the animals received the same management. When possible, the animals were kept until third lactation, giving a total of 514 lactations. Dam weight, dam BCS and calf weight were measured regularly, dam milk production was estimated three times during the lactation and resumption of cyclicity was recorded as well. The experimental data were analyzed using linear models including the effects of heifer efficiency (RFI <-0.4 = efficient; RFI >0.4 = inefficient) and interaction of heifer efficiency and diet group. The data were also used to calibrate a herd dynamics model representing management-nutrition and reproduction interactions at animal level. The experiment data showed that the efficient heifers were 18 kg heavier as cows when fed ad libitum (P = 0.04) but no difference was observed when restricted. Within both diets, heifers classified as efficient produced between 6 and 12 % less milk as cows than inefficient heifers depending on the lactation stage (P < 0.01), with a subsequent effect on calf weight. Finally, the resumption of cyclicity was one week shorter for the efficient animals when fed ad libitum but the opposite was observed within the restricted group, representing a complete ovarian cycle difference between diet groups within the efficient class (P = 0.001). In the lifetime modelling approach, two clusters of animals with different characteristics, including RFI, were simulated under both a non-restricted and restricted feeding environment. In this simulation, efficient heifers produced lighter cows with lower intake and higher body reserves from second calving until culling. Non-efficient heifers had better productive (kg of weaned calf) performance as cows independently of environment. The simulated reproductive performance of cows was equal for animals coming from efficient and non-efficient heifers under the non-restricted environment whereas efficient heifers perform better in the restricted environment, especially when parity increases. Both approaches showed that the interplay between efficiency at young ages and short- and long-term resilience depends on the environment. It can be concluded that the selection for efficiency at young ages has a negative impact on lactational performance as cows but not necessarily on reproductive resilience.

Organic pigs must have permanent access to an open-air space, which typically consists of a barren concrete outdoor run. One way to improve the attractiveness of the outdoor run for pigs and facilitate the establishment of functional zones is through allocation of rooting or roughage materials in this pen area. Accordingly, we investigated the effects of straw (rooting material) and maize silage (roughage) provided under a roof in a concrete-floored outdoor run on the behaviour of organic fattening pigs raised in large groups. In one typical Danish commercial farm, we compared three adjacent, similarly sized pens. Each pen contained an indoor area and an outdoor run. Each outdoor run was divided by a 1 m-high concrete wall into an unroofed area and an area covered by a roof, where substrate could be allocated. One pen received no material under the roof (control), the second pen received straw, and the third pen received maize silage. The study took place from June 2021 to July 2022 and involved 8 batches of pigs. The population size per pen at arrival was (average ± standard deviation) 384 ± 22 pigs, weighing 37 ± 4.8 kg. Pigs were sent to slaughter when their liveweight was approximately 115 kg, approximately 3 months after insertion. Based on footage, the number of pigs present in each area of the outdoor run, and of these the number of pigs in each body posture (lying; sitting; upright) and the number of pigs displaying activity behaviours when standing (exploring the ground; other behaviours than ground exploration) were instantaneously sampled at 10 min intervals from 09:00 h to 16:00 h on days 1, 7, 21, 35, 49, and 63 relative to the batch insertion. More pigs were seen in the roofed area of the outdoor run when either straw or roughage were allocated. Additionally, provision of straw induced more resting in the roofed area whereas allocation of roughage stimulated more ground exploration in the roofed area compared to control pens. Secondarily, pig's activity and outdoor run use were influenced by temporal effects (i.e., experimental day) and weather variations. Thirdly, a pilot study suggested that pigs compete for access to an enriched roofed area. Our study demonstrated the possibility of meeting the behavioural needs - and improving the welfare – of organics pigs housed indoors with access to outdoor run by providing roughage or bedding materials in a roofed area of the outdoor run.